Well
Spfjolietjake already answered for me, but what you said is a problem that lies in what the site define as NTR and what not and also about the use of tags to try to tell users what they will find in a game to decide if it's of their liking or not.
In my super ultra humble and non important opinion is an impossible task, because:
1 A tag is more like a macro that can try to define a general aspect of a fetish but can't comprehend everything ( that's because a single fetish has so widely different expression under a single definition) that it will be impossible to define correctly every single one of said fetish;
2 to be more specific you named a few let's take BDSMas an example: BDSM is a variety of often
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practices or
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involving
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,
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,
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,
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, and other related interpersonal dynamics;
2b: as you can already see this is the bigger definition, it's like an umbrella it cover everything but not in details, if we were to cover every aspects of every singles things in specific terms or tags we should create an infinite number of them and that would be a problem.
3 Why? Even in the remote possibility of being able to do that we would remain with the problem that not always said tags can define the entirety of the content.
4 Why? Because every users ( devs and moderators as well) here have their own knowledge/understanding of the argument and that (more frequently than not) don't match with the result of infinite discussions ( more or less heated) that spread in a large number of pages in the thread.
To summarize, tags are more of a let's say advertisement of what you can possibly find in a game not what you will find in it they need to be generic yet as correct as possible ( utopian, I know) .
But you need to see for yourself and decide if the game content is to your liking or not, and if not express your opinion on that in the more civil and respectful way to see if the dev can improve the aspect you don't see in the content.
I don't know if i was able to explain what I mean, but that's how I see why tags not always can work and how is difficult to define every aspect of a game in a manner that can be useful to the user to find a game that he/she will like to play.